The increasing proportion of six-cylinder engines confirms the sporty, commanding image of the Audi A4. Today, almost every fifth A4 is ordered with a six-cylinder engine. The chart leader is the new 2.5-litre TDI engine.

The world's first six-cylinder diesel engine with direct injection, four valves per cylinder, charge-air intercooling, and a turbocharger with variable turbine geometry has a rated output of 110 kW (150 bhp) and a maximum torque of 310 newton-meters in the engine-speed range from 1,500 to 3,200 rpm. A six-speed manual transmission is standard, but it can also be ordered with 5-speed tiptronic. Both transmission versions are also available with quattro drive.

The tried-and-true four-cylinder TDI power plants developing 66 kW (90 bhp) and 81 kW (110 bhp) remain in the line without change.

The spark-ignition engines for the A4 includes three four-cylinder units rated at 74 kW (101 bhp), 92 kW (125 bhp), and 110 kW (150 bhp), as well as two six-cylinder engines with outputs of 121 kW (165 bhp) and 142 kW (193 bhp).

To achieve greater uniformity in the torque curve and a further reduction in unwanted emissions, the 1.6 and 1.8-litre spark-ignition engines are supplied with air via a variable intake manifold. The 1.8-litre engine with five valves per cylinder also has variable camshaft control for the inlet valves. The high-performance 1.8-litre turbo engine with five valves per cylinder and an output of 110 kW (150 bhp) rounds off the line of four-cylinder spark-ignition engines.

With swept volumes of 2.4 or 2.8 litres, the six-cylinder spark-ignition engines top the Audi A4 model line. Both provide impressive refinement and top performance. They are available with both front-wheel drive and quattro permanent four-wheel drive.

The five-speed tiptronic transmission is available with the Audi A4 2.4 combined with front-wheel drive; the Audi A4 2.8 quattro can also be ordered with tiptronic.

Features shared by all spark-ignition engines with at least 92 kW (125 bhp) on tap are the digital engine management system with electronic "drive-by-wire" accelerator and five valves per cylinder.

Three intake and two exhaust valves ensure optimum gas flow - the engine breathes particularly well. This makes it possible to achieve high power and torque combined with lower fuel consumption and exhaust emissions. Audi was the first company to offer engines with five valves per cylinder in volume-produced cars.

An engine management system of the latest type calculates all requirements imposed on the engine and converts them into torque requests. For a fast and spontaneous reaction, it uses the electronic throttle as an additional adjustment variable until the optimum operating point is reached.

1999 Mid-Year Changes Introduction
Design: sporty and elegant
Inner beauty as well
Progressive infotainment
Extensive chassis modifications
Safety and SIDEGUARD
Varied choice of engines

The equipment specification and data given refer to models available in Germany. Audi reserves the right to make changes. Errors and omissions excepted.

Copyright (c) 1999 AudiWorld